Q. Plants showing `C_(4)` photosynthesis have

Options

A. a) Granal bundle sheath chloroplasts and agranal mesophyll chloroplasts
B. b) Agranal bundle sheath chloroplasts and granal mesophyll chloroplasts
C. c) Both bundle sheath and mesophyll chloroplasts are agranal
D. d) Both the type of chloroplasts are granal.

Answer

To answer the question regarding the role of Magnesium, Calcium, and Fluorine in photosystem II, we can break down the solution step by step.

### Step-by-Step Solution:

1. **Understanding Photosynthesis**: Photosynthesis occurs in two main stages: the light-dependent reactions and the light-independent reactions (Calvin cycle). The light-dependent reactions take place in the thylakoid membranes of chloroplasts and involve the absorption of light and the splitting of water.

2. **Role of Photosystems**: In the light-dependent reactions, two photosystems are involved: Photosystem I (PSI) and Photosystem II (PSII). PSII absorbs light at a wavelength of around 680 nm and is crucial for the initial steps of photosynthesis.

3. **Photolysis of Water**: One of the key processes occurring in PSII is the photolysis of water. This is the splitting of water molecules (H₂O) into oxygen (O₂), protons (H⁺), and electrons (e⁻) using light energy.

4. **Importance of Minerals**: The minerals Magnesium, Calcium, and Chlorine play a vital role in the function of PSII. Specifically, they are involved in the process of photolysis.
- **Magnesium** is a central atom in chlorophyll, which is essential for light absorption.
- **Calcium** is involved in stabilizing the structure of the thylakoid membranes and is also crucial for the activity of various enzymes.
- **Chlorine** (often referred to as Cl⁻) is involved in the water-splitting complex of PSII.

5. **Conclusion**: Given the roles of these minerals, the correct answer to the question is that they are important for the **photolysis of water** (Option C).

### Final Answer:
Plants showing C₄ photosynthesis have minerals like Magnesium, Calcium, and Chlorine that play an important role in the photolysis of water.

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